Variable stroke feeder for moving refuse and like compactable material

ABSTRACT

The disclosure is directed to a variable stroke mechanical feeder for compacting and moving of municipal mixed refuse over the insulated hearth of a combustion furnace. As the degree of compaction of such mixed refuse increases, the resistance of the refuse to moving over the insulated hearth of the furnace also increases. This increased resistance has been overcome by selectively increasing the length of stroke of the feeder.

United States Patent [72] Inventors Bertram B. Reilly 17 Briar Cliff Road, Pittsburgh, Pa. 15202; Milton F. Guy, 8148 Halcyon Court,

Grosse Ile, Mich. 48138 [21] Appl. No. 815,423 [22] Filed Apr. 11, 1969 [45] Patented Feb. 16, 1971 [54] VARIABLE STROKE FEEDER FOR MOVING REFUSE AND LIKE COMPACTABLE MATERIAL 7 Claims, 3 Drawing Figs. [52] US. Cl 214/23; 100/50; 110/109; 193/225 [51 Int. Cl. F23k 3/00 [50] Field of Search 214/17.6,

[ 56] References: Cited UNITED STATES PATENTS 3,161,305 12/1964 Ferrari et a1 214/82 3,303,947 2/1967 Reilly 214/23 Primary Examiner-Robert G. Sheridan Attorney-Parmelee, Utzler & Welsh ABSTRACT: The disclosure is directed to a variable stroke mechanical feeder for compacting and moving of municipal mixed refuse over the insulated hearth of a combustion furnace. As the degree of compaction of such mixed refuse increases, the resistance of the refuse to moving over the insulated hearth of the furnace also increases. This increased resistance has been overcome by selectively increasing the length of stroke of the feeder.

PATENTED FEB 1 s 971 am 2 [1F 2 mvembn BERTRAM 8. RE/LL Y Micro/v IF Guy Attorneys VARIABLE STROKE FEEDER FOR MOVING REFUSE AND LIKE COMPACTABLE MATERIAL FIELD OF THE INVENTION This invention relates to a feeder for moving large amounts of compactible material, such as refuse, from one enclosure to another, as where municipal refuse is moved from a receiving bin into an incinerator.

DESCRIPTION OF THE PRIOR ART The present invention is an improvement over the fixed length of stroke feeder of U.S. Pat. No. 3,303,947.

BACKGROUND AND PURPOSE OF THE INVENTION The present invention is particularly adapted to the feeding or the moving of refuse from a receiving bin into an incinerator and it will be described herein for such purpose. However, the invention may be used to feed other materials or be used in other environments which involve like or similar problems.

In moving or feeding large volumes of compactible material, such as municipal refuse from a receiving bin into an incinerator, it is desirable, due to the varied nature of the material, to push it through a confined channel or passageway. By feeding the material in this manner a compacted refused seal or plug is maintained in the passageway between the bin and the incinerator. A feeder apparatus is shown in U.S. Pat. No.

r 3,303,947 issued Feb. 14, I967 for accomplishing such feeding. A difficulty in feeding municipal refuse or the like by the apparatus as described in the above patent is the frictional resistance offered by the material to being pushed through the confined passageway with the result that as the resistance increases, the compaction of the material being moved increases, thereby further increasing the resistance to its movement. Due to this resistance, after a period of operation of the feeder, an extremely compact plug of material may develop in the passageway which will resist movement along the passageway to such a degree that the feeder will become inoperative to advance the plug of material along the passageway and into the incinerator.

The present invention seeks to overcome this problem by providing a pusher wherein the feeding or in-stroke" length of the pusher may be controlled and varied.

SUMMARY OF THE INVENTION Briefly, the present invention provides a bin having a bottom, side and end walls for retaining a supply of compactible material, and a pusher arranged at the bottom of the bin which is sequentially movable from a retracted position adjacent one end wall of the bin toward and through a discharge opening in another end wall of the bin. The discharge opening in the bin leads into a passageway, typically the feed opening pf an incinerator, having a bottom, top and sidewalls with the bottom of the discharge opening and of the passageway being flush with the bottom of the bin. The pusher is arranged to be moved into selectively predetermined first and second positions within the passageway. Power means comprising at least one hydraulic ram is arranged for effecting movement of the pusher. First means are operatively connected to the power means for controlling it and thus movement of the pusher between its retracted position and' the first or second positions. The normal sequence of operation of the pusher is between the retracted position and the first position such that the lowermost mass of material at the bottom of the bin is pushed through the discharge opening and into the passageway with each cycle of operation of the pusher exerting a compacting effect against similarly previously pushed material to form a plug of material in the passageway which is normally moved along the passageway by such pushing. A plug which fills the passageway is desirable in an incinerator to prevent flashback of flames or escape of smoke and fumes through the feed opening. Second means are operatively connected to the power means and are responsive to the plug of material encountering a predetermined resistance to further movement along the passageway for interrupting the normal sequence and causing the pusher to move beyond the first position and toward the second position thereby resulting in the plug of material being advanced along the passageway a greater distance than it would have been in the normal sequence of operation of the pusher.

This latter movement of the pusher assures that the feeder is effective for moving the material along the passageway and into the incinerator while maintaining a seal or plug between the bin and the incinerator.

A more complete understanding of the present invention will become apparent from the following description, taken in conjunction with the accompanying drawings showings only a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 represents a plan view of the pusher-type feeder arrangement of the present invention at the charging end of an incinerator;

FIG. 2 is a vertical longitudinal sectional view of the pushertype feeder arrangement shown in FIG. 1; and

FIG. 3 shows an electrical circuit for controlling operation of the pusher-type feeder arrangement shown in FIGS. I and DESCRIPTION OF THE PREFERRED EMBODIMENT In the drawings, wherein like reference numerals refer to like parts throughout the several views, there is shown somewhat schematically the forward or charging end of an incinerator A, with a horizontal charging passage 2, in the front wall B thereof. This charging passage is generally rectangular in cross section, being wider than it is high. It has a refractory bottom wall or floor 3, side walls 4, and a top wall 5. At 6 there is an upwardly and inwardly movable door, movable from the open position as shown in the drawings to a closed position blocking the passageway 2. A suitable fluid pressure actuated cylinder and piston mechanism 7 is here indicated for moving the door, between open and closed position.

Rearwardly of the charging door there is a suitable refuse receiving bin C. The bin C has suitable sidewalls 10, 10a, 10b and a metal bottom 11 aligned with floor 3 of the passage 2. The bin end wall 10a has a discharge opening 11b communicating with the passageway 2 and the wall opposite the incinerator opening is designated 10b. At the bottom of the bin there is a pusher indicated generally as 12. The pusher 12 comprises a vertical refuse engaging front or pusher face I3. At the rear of the pusher face 13 there is attached a pair of transversely spaced rams, each having a fixed cylinder 14 and a movable plunger 16, the forward ends of which are attached to the pusher at 17. A suitable apron plate 18 is secured at one end to pusher l2 and extends rearwardly therefrom to cover the plungers 16 from contact with refuse in bin C.

When the pusher face 13 is in fully retracted position as at R, it is disposed beneath the rear face 10b of the refuse bin C and refuse within bin C falls upon the forehearth II of incinerator A beneath the bottom opening of the bin. Suitable fluid pressure lines to cylinders 14 advance the pusher face 13 forward and towards the incinerator A, so as to compact the refuse from the bin C and feed same into the furnace. Compacted refuse moving over the refractory hearth 3 to the furnace generates considerable resistance therefrom and may plug the opening 2 into the incinerator. Certain types of refuse tends to compact more readily than others and such compaction increases the frictional resistance of the refractory forehearth to movement of the compacted refuse thereover. When this occurs the feeding operation is stopped.

To overcome such conditions I have provided a variable feeding stroke to pusher 13, whereby the length of stroke of pusher I3 is extended after encountering a predetermined resistance to movement of the compacting material and before the frictional resistance of the compacting material is of such a degree as to stop further feeding operations.

Referring now to FIGS. 2 and 3 of the drawing, at the starting of the refuse feeding operation to the furnace A, the door 6 is in the open position as shown in FIG. 2. Fluid pressure is supplied from a suitable means not shown, and control of the feeding of fluid pressureto cylinders 14 is controlled by means of solenoid actuated valves which in turn are controlled through various limit switches. These limit switches and solenoid valves, except for the illustration in FIG. 3, have not been shown in FIGS. 1 and 2, for purposes of clarity.

With reference to FIG. 3, the limit switches LS1 and LS-2 are actuated by the pusher 12 when it moves forward. LS-3 is actuated when the pusher retracts. SV-R designates the reverse solenoid valve which when energized permits fluid to enter the forward ends of cylinders 14 to retract the pusher l2. SV-F designates the forward solenoid valve which when energized permits fluid to enter the rear ends of cylinders 14 to advance the pusher 12. It will be apparent to those skilled in the art that the limit switches LS-l and LS-2 are of the normally open type and that LS-3 is of the normally closed type.

The relay shown controls operation of contacts RC-1 and RC-2, which are normally open, and RC3 is of the normally closed type. A pressure responsive switch PS is shown which is normally closed but which will open at a predetermined fluid pressure in the cylinders 14, and a momentary switch MS is shown, the functionof which will be apparent as the description proceeds.

In the condition shown, SV-F is energized through normally closed contacts RC 2. Accordingly, the plungers 16 will move forward moving pusher 12 forward until it reaches the position shown in FIG. 2. At that time, normally open LS-l closes and energized the relay through the normally closed pressure switch PS and normally closed momentary switch MS. Upon the energization of the relay, normally closed contacts RC-Z opens which deenergizes SV-F stopping forward movement of the plungers l6, and normally open contacts RC1 close which energizes SV-R through normally closed LS-3 causing the plungers to reverse which retracts the pusher 12. As the plungers 16 reverse, LS-l returns to its normally open condition, however, the relay remains energized through normally closed LS-3 and latching contacts RC-3 which were closed upon the energization of the relay. When the plungers 16 are fully retracted and the pusher 12 retracts to the dotted line position R shown in H6. 2, LS3 opens which deenergizes the relay causing contacts RC-l to revert to their normally open condition which deenergizes SV-R stopping the reverse movement of the plungers 16. Also, with the relay deenergized, contacts RC-2 revert to their normally closed condition and energizes SV-F causing the plungers l6 and pusher 12 to move forward. As the pusher moves forward, LS-3 reverts to its normally closed condition and the above cycle repeats itself.

The above-described sequence continues until the plug of compacted material encounters a predetermined resistance to further movement along the passageway 2. lf the pusher l2 meets such a resistance to forward movement prior to LS-l opening and effecting reverse movement of the pusher 12, the pressure switch PS will open due to the buildup of pressure in the cylinders 14. Due to the increased pressure in cylinders 14, the pusher will continue to move forward, however, when the pusher 12 reaches the first position shown in FIG. 2 and effects closing of LS-l, the relay will not be energized because pressure switch PS is now open. Therefore, contacts RC-2 will remain closed maintaining SV-F energized and the pusher will continue to move forward. However, when the pusher reaches the dotted line position 13, LS-2 will close and the relay will be energized through LS-2 and the momentary switch MS. With the relay energized, RC-Z will open and forward movement of the pusher 12 will stop. Continued operation of the control circuit is as above-described and the pusher 12 will now be moved back to its retracted position R.

From the foregoing, it will be seen that normal sequence of feeding material into the incinerator will be interrupted when the plug of material encounters a predetermined resistance to movement along the passageway 2 and that the pusher 12 will move beyond the first position and toward the second position which is in advance of the first position, thereby resulting in the plug of material being advanced along the passageway 2 a greater distance than it would have been in the normal sequence of operation of the pusher 12.

It may also be pointed out that if the normal sequence has been interrupted, i.e. LS-l closed'and pressure switch PS open, and for any reason the pressure in cylinders 14 drops below that required to open pressure switch PS and before LS2 is closed to effect reverse movement of the pusher 12, the pusher 12 will also reverse. This is because LS-l is closed and when pressure switch PS closes due to the drop in pressure, the relay will be energized which effects opening of contacts RC-2 and deenergization of SV-F.

The momentary switch MS when opened renders the limit switches LS-1 and LS-2 inoperative to control operation of the plungers. This switch permits manual extension of the plungers to their full stroke length for clearing off the floor 3 at the end of an operating period.

We claim:

1. The combination with a bin having bottom, side and end walls for retaining a supply of compactible material, said bin having a discharge opening in one end wall thereof leading into a passageway having a bottom, sides and top walls with the bottom of the discharge opening and of the passageway being flush with the bottom of the bin, a pusher at the bottom of the bin movable from a retracted position adjacent the other end wall of the bin toward and through said discharge opening into selectively predetermined first or second positions within said passageway, power means for effecting movement of said pusher and means operatively connected to said power means for controlling the movement of said pusher to either of the first or second positions, said latter means including means responsive to the pusher encountering a predetermined resistance to movement prior to its having advanced to the first position for effecting movement of the pusher to the second position.

2. The combination as defined in claim 1 wherein said bottom of the passageway is located inside an incinerating furnace.

3. The combination as defined in claim 1 wherein said power means comprises at least one hydraulic ram having a cylinder fixed relative to said pusher and a movable plunger attached to said pusher.

4. The combination with a bin having a bottom, side and end walls for retaining a supply of compactible material, said bin having a discharge opening in one end wall thereof leading into a passageway having a bottom and sides with the bottom of the discharge opening and of the passageway being flush with the bottom of the bin, a pusher at the bottom of the bin sequentially movable from a retracted position adjacent the other end wall of the bin toward and through said discharge opening into selectively predetermined first or second positions within said passageway, power means for effecting movement of the pusher, first means operatively connected to the power means for controlling said power means and thus sequential movement of said pusher between said retracted position and said first or second positions, the normal sequence of operation of the pusher being between said retracted position and said first position, and second means operatively connected to the power means and responsive to said pusher encountering a predetermined resistance to movement prior to its having advanced to said first position for interrupting said normal sequence and causing said power means to move said pusher beyond said first position and toward said second position.

5. The combination with a bin having bottom, side and end walls for retaining a supply of compactible material, said bin having a discharge opening in one end wall thereof leading into a passageway having a bottom and sidewalls with the bottom of the discharge opening and of the passageway being flush with the bottom of the bin, a pusher at the bottom of the bin sequentially movable from a retracted position adjacent the other end wall of the bin toward and through the discharge opening into selectively predetermined first or second positions within said passageway, power means for effecting movement of said pusher, first means operatively connected to the power means for controlling said power means and movement of said pusher between said retracted position and said first or second positions, the normal sequence of operation of the pusher being between said retracted position and said first position such that the lowermost mass of material at the bottom of the bin is pushed through the discharge opening and into the passageway, each sequence of operation of the pusher exerting a compacting effect against similarly pushed material to form a plug of material in the passageway which is normally moved along the passageway by such pushing, and second means operatively connected to said power means and responsive to said plug of material encountering a predetermined resistance to further movement along said passageway for interrupting said normal sequence and causing said pusher to move beyond said first position and toward said second position, said second position being in advance of said first position thereby resulting in said plug of material being advanced therealong the passageway a greater distance than it would have been in the normal sequence of operation of said pusher.

6. The combination as defined in claim 5 wherein said bottom of the passageway is located inside an incinerating furnace.

7. The combination as defined in claim 5 wherein said power means comprises a pair of hydraulic rams, each ram having a cylinder fixed relative to said pusher and a movable plunger attached to the pusher. 

1. The combination with a bin having bottom, side and end walls for retaining a supply of compactible material, said bin having a discharge opening in one end wall thereof leading into a passageway having a bottom, sides and top walls with the bottom of the discharge opening and of the passageway being flush with the bottom of the bin, a pusher at the bottom of the bin movable from a retracted position adjacent the other end wall of the bin toward and through said discharge opening into selectively predetermined first or second positions within said passageway, power means for effecting movement of said pusher and means operatively connected to said power means for controlling the movement of said pusher to either of the first or second positions, said latter means including means responsive to the pusher encountering a predetermined resistance to movement prior to its having advanced to the first position for effecting movement of the pusher to the second position.
 2. The combination as defined in claim 1 wherein said bottom of the passageway is located inside an incinerating furnace.
 3. The combination as defined in claim 1 wherein said power means comprises at least one hydraulic ram having a cylinder fixed relative to said pusher and a movable plunger attached to said pusher.
 4. The combination with a bin having a bottom, side and end walls for retaining a supply of compactible material, said bin having a dischargE opening in one end wall thereof leading into a passageway having a bottom and sides with the bottom of the discharge opening and of the passageway being flush with the bottom of the bin, a pusher at the bottom of the bin sequentially movable from a retracted position adjacent the other end wall of the bin toward and through said discharge opening into selectively predetermined first or second positions within said passageway, power means for effecting movement of the pusher, first means operatively connected to the power means for controlling said power means and thus sequential movement of said pusher between said retracted position and said first or second positions, the normal sequence of operation of the pusher being between said retracted position and said first position, and second means operatively connected to the power means and responsive to said pusher encountering a predetermined resistance to movement prior to its having advanced to said first position for interrupting said normal sequence and causing said power means to move said pusher beyond said first position and toward said second position.
 5. The combination with a bin having bottom, side and end walls for retaining a supply of compactible material, said bin having a discharge opening in one end wall thereof leading into a passageway having a bottom and sidewalls with the bottom of the discharge opening and of the passageway being flush with the bottom of the bin, a pusher at the bottom of the bin sequentially movable from a retracted position adjacent the other end wall of the bin toward and through the discharge opening into selectively predetermined first or second positions within said passageway, power means for effecting movement of said pusher, first means operatively connected to the power means for controlling said power means and movement of said pusher between said retracted position and said first or second positions, the normal sequence of operation of the pusher being between said retracted position and said first position such that the lowermost mass of material at the bottom of the bin is pushed through the discharge opening and into the passageway, each sequence of operation of the pusher exerting a compacting effect against similarly pushed material to form a plug of material in the passageway which is normally moved along the passageway by such pushing, and second means operatively connected to said power means and responsive to said plug of material encountering a predetermined resistance to further movement along said passageway for interrupting said normal sequence and causing said pusher to move beyond said first position and toward said second position, said second position being in advance of said first position thereby resulting in said plug of material being advanced therealong the passageway a greater distance than it would have been in the normal sequence of operation of said pusher.
 6. The combination as defined in claim 5 wherein said bottom of the passageway is located inside an incinerating furnace.
 7. The combination as defined in claim 5 wherein said power means comprises a pair of hydraulic rams, each ram having a cylinder fixed relative to said pusher and a movable plunger attached to the pusher. 